Multifocal cysts and incidence of pancreatic cancer concomitant with intraductal papillary mucinous neoplasm.

OBJECTIVES:The present study was conducted in order to elucidate the relationship between the number of cyst-existing regions and incidence of pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN), which currently remains unclear. METHODS:Subjects comprised 141 patients undergoing resection for IPMN (Non-invasive IPMN (IPMN with low-to high-grade dysplasia): N = 94, invasive IPMN: N = 31, and PDAC concomitant with IPMN: N = 16) between November 2000 and February 2017. A logistic regression analysis was performed to assess the relationship between the number of cyst-existing regions (one region/two or more regions) and incidence of PDAC concomitant with IPMN, adjusted by clinical characteristics. Cyst-existing regions were defined by the number of anatomical parts of the pancreas: the head/body/tail of the pancreas. RESULTS:Multiple cyst-existing regions (two or more regions) correlated with the incidence of PDAC concomitant with IPMN (PDAC concomitant with IPMN in one region vs. two or more regions: 3/66 vs. 13/75, multivariable odds ratio [OR] = 4.11, 95% confidence interval [CI] = 1.22 to 18.8, P = 0.02). In contrast, multiple cyst-existing regions did not correlate with the incidence of IPMN (invasive IPMN in one region vs. two or more regions: 13/66 vs. 18/75, OR = 1.19, 95% CI = 0.52 to 2.76, P = 0.67). CONCLUSIONS:Multifocal cysts correlated with the incidence of PDAC concomitant with IPMN, and may be a high-risk factor for PDAC concomitant with IPMN.